Procedure Before the first lab session, the participants will be stratified randomly assigned to one of the three groups. All participants will visit the lab 17 times. During the first visit, participants will fill in an informed consent, demographic information and questionnaires. They will continue with a training for the letter string interference task to avoid learning effects. At the end of the first visit, EEG resting state will be measured. During the second and third visit, participants will only receive a resting state EEG measurement and perform the letter string interference task. In the sessions after these baseline measurements, participants will receive a 4 minute EEG eyes-open resting state measurement, following either TBR Neurofeedback training or a placebo training depending on the participant group. After the Neurofeedback training, resting state measurement or placebo training, participants will always perform the letter string interference task. Sessions will be (almost) daily and approximately take between 50-60 minutes; except for the first questionnaires/interference training session which will take 90 minutes. The complete experiment will therefore take 17-19 hours per participant in 4-6 weeks.